Gre·go·ri·an chant /ɡrɪˌɡɔːriən ˈtʃɑːnt $ -ˈtʃænt/
noun [uncountable and countable][
Date: 1700-1800;
Origin: Because it is said to have been introduced by Pope Gregory I]
a kind of church music for voices alone
[TahlilGaran] Dictionary of Contemporary English ▲